MLA

Gillray, James, 1756-1815, printmaker. Evidence to character, being a portrait of a traitor by his friends & by himself [graphic]. [1 October 1798]. https://collections.library.yale.edu/catalog/10941223.

APA, 6th edition

Gillray, James, 1756-1815, printmaker. ([1 October 1798])[Evidence to character, being a portrait of a traitor by his friends & by himself [graphic]]. https://collections.library.yale.edu/catalog/10941223.